Refrigeration cabinet



Aug. 30, 1966 D. e. HARTER REFRIGERATION CABINET 2 Sheets-Sheet 1 Filed Oct. 15, 1965 2728 FIG. 4

R m R /1 N NA R WH m m J, 0 VA "A N 2 Sheets-Sheet 2 Aug. 30, 1966 D. G. HARTER REFRIGERATION CABINET Filed Oct. 15, 1963 United States Patent 3,269,787 REFRIGERATION CABINET Donald G. Harter, Etlina, Minn, assignor to Studebaker Corporation, South Bend, Ind, a corporation of Michigan Filed Oct. 15, 1963, Ser. No. 316,412 2 Claims. (Cl. 312-116) This invention relates generally to refrigerated food display and vending cabinets having an open-top food case, and more particularly, it relates to an improved cabinet cover and related structure therefor.

Refrigeration cabinets of the type to which this invention relates normally comprise spaced end walls and front and rear walls which define an open-top food case, the rear wall being of greater height than the end walls, and the rear portions of the end walls having upwardly directed extensions. Also, a top wall normally extends between the upper portions of the end wall extensions and defines with the rear wall a forwardly opening housing which overlies the rear portion of the food case.

An important object of the present invention is the provision of a cabinet cover for refrigerated display cabinets, and which cabinet cover has top wall, front wall and end walls formed as an integral one-piece unit for greater strength and for better product display and visibility.

With previously known types and constructions of cabinet covers for refrigerated display cabinets, the same have been often characterized by a binding and uneasy movement of the cabinet cover between its operative and inoperative positions. A further problem has been the moisture condensation and formation of frost on the inner surface of the cabinet cover when the same is in its operative position. In view of these problems, another impor tant object of the present invention is the provision of a construction for cabinet covers of refrigerated display cabinets which overcomes entirely or greatly alleviates the above-noted problems.

More particularly, an object of the present invention is the provision of a cabinet cover for refrigerated display cabinets which is mounted for sliding movements between an inoperative storage position within the cabinet housing and an operative position covering the open top of the food case by means of wheel-equipped carriages at the opposite ends of the cover and an adjustable center guide roller intermediate the opposite ends of the cover.

Another object of the present invention is the provision of a cabinet cover for refrigerated display cabinets which includes heating means carried by the cabinet and positioned to direct a flow of warm air over the outer surface of the top wall of the cover when the same is in its operative position so as to prevent the condensation of moisture on the inner surface of the cover.

A still further object is the provision of a cabinet cover for refrigerated display cabinets which includes exterior heating means carried by the cabinet and positioned to direct a flow of warm air over the outer surface of the top wall of the cover and which further includes interior heating means carried by the cabinet adjacent the open top of the food case and positioned and arranged to direct a flow of warm air across the inner surface of the cover when the same is in its operative position whereby to prevent the condensation of moisture and the formation of frost on the inner surface of the cover when it is in its operative position.

The above and still further objects and advantages of the present invention will become apparent from a consideration of the following detailed specification, appended claims and attached drawings.

Referring to the drawings, wherein like reference characters indicate like parts or elements throughout the several views:

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FIG. 1 is a view in front elevation showing a refrigeration cabinet having the novel cabinet cover construction of the present invention, some parts being broken away, some parts shown in section, and some parts being shown by dotted lines;

FIG. 2 is a view in end elevation of the left hand of the cabinet relative to FIG. 1, some portions being shown by dotted lines;

FIG. 3 is a fragmentary detailed view showing a rear elevation of the blower;

FIG. 4 is an enlarged view in horizontal section taken on the line 44 of FIG. 2, portions thereof being broken away;

FIG. 5 is an enlarged view in vertical section taken on the line 5-5 of FIG. 1;

FIG. 6 is an enlarged view in section taken on the broken line 66 of FIG. 2 with intermediate portions of the view being broken away;

FIG. 7 is an enlarged detailed view in vertical section taken on the line 7--7 of FIG. 1;

FIG. 8 is an exploded view in perspective of the mounting carriage for one end portion of the cabinet cover;

FIG. 9 is a view in perspective of the retainer cap for the opposite end portions of the cabinet cover;

FIG. 10 is a view in perspective of the supporting rail for the opposite end portions of the cabinet cover, some portions being broken away; and

FIG. 11 is a schematic circuit diagram.

Referring to the drawings, the refrigeration cabinet dis closed herein includes a bottom frame and supporting structure 1, opposed end walls 2, 3, a front wall 4 and a rear wall 5. The end wall 2 comprises an inner panel 6 and an outer panel 7, the end wall 3 has an inner panel 8 and an outer panel 9, the front wall 4 has an inner panel 10 and an outer panel 11, and the rear wall 5 also includes an inner panel 12 and an outer panel 13. As shown particularly in FIG. 6, the end wall 2 includes a top cap 14 between its inner and outer panels, and the end wall 3 includes a top cap 15, the front wall 4 including a top cap portion 16, as shown particularly in FIG. 5. Also, the spaces between the inner and outer panels of the cabinet walls are filled with a suitable thermal insulation material 17 in the conventional manner.

As shown particularly in FIGS. 1 and 2, the rear wall 5 of the cabinet extends above or is greater in height than the cabinet front wall 4, and the rear portions of the cabinet end walls 2, 3 define upwardly directed wall extensions 18, 19, respectively. The end wall extensions 18, 19 are not insulated and include the outer panels 7, 9 of the end walls 2, 3 which have downwardly and forwardly extending front edge portions provided with trim strips 20.

The refrigeration cabinet structure further includes a top wall 21 which extends between the upper portions of the end wall extensions 18, 19, as shown particularly in FIGS. 1 and 5. The top wall 21 includes generally parallel vertically spaced upper and lower panels 22, 23 and a front edge panel 24 extending therebetween. The top wall 21 defines with the end wall extensions 18, 19 and the cabinet rear wall 5 a forwardly opening housing, indicated generally by the reference numeral 25, which generally overlies the rear portion of the food case defined by the cabinet walls. Visibility of the contents of the food chamber or food case defined by the cabinet walls is provided by a front panel formed of a plurality of glass plates 26 or other suitable transparent sheet material. The transparent front panel is positioned at and forms a part of the top of the cabinet front wall 4 and is secured thereto by means of suitable mounting strips, as shown particularly'in FIGS. 1 and 5.

As shown particularly in FIG. 5, the cabinet structure further comprises a generally cross-sectionally inverted U-shaped insulating frame structure, represented generally by the reference numeral 27, which overlies the rear portion of the food case and the evaporator unit of the refrigeration apparatus. The insulating frame structure 27 includes an upper wall 28, a lower wall 29, a depending front portion including an outer wall 30, an inner wall 31 and a lower edge panel 32. The insulating frame structure 27 defines the lower extremity of the abovenoted forwardly opening housing 25. The upper chamber defined by the insulating frame structure contains a portion of the evaporator unit 33 of the cabinet refrigeration apparatus. The remainder of the refrigeration apparatus is not shown, but will be understood to include the usual components of a compressor, condenser and suitable controls. As shown in FIG. 5, the evaporator unit 33 is a fin-type expansion coil unit having vertically spaced stages and including a plurality of evaporator tubes 34 and a plurality of vertically disposed fins 35 connected in laterally spaced relationship to the evaporator tubes 34. Also, a drain pan 36 is disposed below the evaporator unit 33 to collect the condensate or water coming from the same during defrost thereof and the condensate or water is directed from the drain pan 36 through a suitable discharge tube 37 and into a container, not shown. It is noted that additional evaporator tubing, partially shown at 36a in FIG. 5, is secured to the outer surfaces of the inner panels 6, 8, and 12 of the food case.

The present invention resides in the provision of a slidable cabinet oover, represented generally by the reference numeral 38, and related structure for the refrigerated display cabinet described herein. The cabinet cover 38 is positioned to overlie the open top of the above-noted food case, and the cover 38 includes an elongated slightly curved top wall 39, a front wall 40 and opposed end Walls 41, 42. The top wall, front wall and end walls of the cabinet cover are formed, as by molding, from a suitable transparent plastic material and in an integral one-piece unit, as shown in the drawings.

Referring particularly to FIGS. 6 and 10, a pair of elongated supporting rails 43 are one each secured to the top cap 14, of a different one of the cabinet end walls 2, 3. The elongated supporting rails 43 are generally C-shape in cross section to define a corner opening throughout their length. The cabinet cover 38 is mounted for sliding movements relative to the supporting rails 43 between an inoperative storage position, not shown, but within the forwardly opening housing 25 and an operative position shown in the drawings and forwardly of the housing to cover the open top of the food case, as shown particularly in FIGS. 5 and 7 of the drawings. When the cover 38 is in its inoperative position, the front wall 40 thereof engages a pair of rubber bumpers 40a carried by the frame structure 27. The cabinet cover 39 is mounted relative to the supporting rails 43 by means of a pair of wheel-equipped carriages 44, one each secured on the lower edge portion 45 of a different one of the end walls 41, 42 of the cover 38. The carriages 44 include a vertical plate portion 46 secured by suitable fasteners 47 to the cover 38, as above noted, and further include a depending flange 48 for mounting a pair of horizontally spaced vertical rollers 49. Each of the carriages 44 further includes a pair of horizontally spaced tab flanges 50 one each positioned at the opposite end portions of the carriages 44 for mounting a pair of horizontal rollers 51. The vertical plate portions 46 of the carriages extend through the corner slots of the associated supporting rails 43, as shown particularly in FIG. 6. The vertical rollers 49 of the carriages 44 are adapted to roll or ride on the horizontal flanges 52 of the supporting rails 43, and the horizontal rollers 51 are arranged and positioned to engage the vertical outer flanges 53 of the supporting rails 43.

Center guide means is also provided for mounting and carrying the cabinet cover 38, the same including an elongated generally horizontal center rail 54 secured to the lower panel 23 of the cabinet top wall 21 by suitable fasteners 55 and located generally intermediate the opposite end walls 41, 42 of the cover 38 and the end walls 2, 3 of the cabinet. The center rail 54 is generally C-shaped in cross section and is adapted to receive an upstanding center guide roller 56 journalled on the top wall 39 of the cabinet cover 38 adjacent the rear edge portion 57 thereof. The center guide roller 56 is particularly useful in preventing binding of the cover 38 during its freely moving transfer between its operative and inoperative positions.

Referring particularly to FIG. 5, it Will be noted that the cabinet cover 38 defines a depending front flange 58 adapted to abut against and engage an inner edge surface of the front wall 4 when the cover 38 is in its operative position. A handle 59 is provided on the front wall 40 of the cabinet cover 38 for conveniently moving the cover 38 between its operative and inoperative positions noted above. A pair of retainer caps 60, the construction of which is shown particularly in FIG. 9, are one each secured by means of a suitable fastener 61 to the top caps 14, 15 of a different one of the cabinet end walls 2, 3. Each of the retainer caps defines an elongated slot 62 to receive the front edge portion 63 of the carriages 44 and thereby define the forward limits of the operative position of the cover 38. The retainer caps 60 also operate to retain the carriages 44 of the cabinet cover 38 within the supporting rails 43, and it is noted that the cover 38 may be easily removed from the cabinet merely by removing the retainer caps 60 and lifting upwardly on the cover 38 to raise the depending flange 58 thereof above the cabinet front wall 4.

An important feature of the present invention is the provision of means for preventing the condensation of moisture and the formation of frost on the inner surface of the cabinet cover 38 when in its operative position shown in the drawings. Therefore, in accordance with the present invention, heating means is provided in combination with the cabinet for directing a flow of warm air over the surfaces of the cabinet cover 38 when the same is in its operative position. More particularly, exterior heating means is provided by a pair of heating elements 64 positioned in the space between the upper and lower panels 22, 23 of the cabinet top wall 21, as shown particularly in FIG. 5. More particularly, the heating elements 64 are secured to the upper surface of an elongated louver plate 65 secured to the lower panel 23 of the cabinet top wall 21. The above-noted exterior heating means further comprises a centrifugal or axial blower 66 sui-tably mounted on the cabinet rear wall 5, as shown particularly in FIGS. 3 and 5. The blower 66 includes a scroll casing 67 which defines an axial inlet 68 and which connects with an outlet duct 69 leading to the space between the upper and 'lower panels 22, 23 of the top wall 21, as shown particularly in FIGS. 3 and 5 of the drawings. The impeller or fan wheel 70 of the blower 66 operates to circulate the air over the heating elements 64, through the louvers of the louver plate 65 and across the outer surface of the cover top wall 39, as shown by arrows in FIG. 5.

The novel heating means provided in accordance with this invention for preventing the condensation of moisture and formation of frost on the cabinet cover 38 further inoludes interior heating means carried by the cabinet adjacent the open top of the above-noted food chamber or food case. The interior heating means is positioned and arranged to direct a flow of warm air across the inner surfaces of the cabinet cover 38 when the same is in its operative position. The interior heating means comprises an electrical heating element 71 secured by suitable clips to the upper portion of the glass panel 26 of the front wall 4, as shown particularly in FIGS. 1, 4, and 5. The heating element 71 is thereby positioned adjacent the front wall 40 of the cabinet cover 38 for providing an upward flow of warm air across the inner surface of the front wall 40 of the cover 38 when the same is in its operative position, as shown by the arrows in FIG. 5.

The interior heating means for the cabinet cover 38 further includes a second heating element 72 having verticall-ly spaced sections which are secured by suitable clips to the inner surface of a depending partition panel 73 disposed forwardly of the insulating frame structure 27, as shown particularly in FIG. 5, so as to be positioned adjacent the rear portion of the cabinet cover 38 when the same is in its operative position. As shown by arrows in FIG. 5, the second heating element 72 is thereby positioned and arranged to direct warm air forwardly across the inner surface of the top wall 39 of the cover 38. As seen in FIGS. 1 and 5, lights 73a are carried by the partition panel 73 for lighting the food case and also for an auxiliary heat supply.

In accordance with this invention, switch means is provided for de-energizing the above-noted heating means when the cabinet cover 38 is moved to its inoperative position within the forwardly opening housing 25. In accordance with present practices, a cover-actuated switch 74 is positioned within the housing 25 and adjacent the cabinet rear wall 5 and further located so as to be engaged by the end wall 41 of the cover 38 upon movement of the cover 38 to its inoperative position so as to break the circuit. The switch 74 is interposed in the line which provides electrical power to the blower motor 75 and the heating elements 64, 71 and 72. According to the present arrangement, the blower motor 75 is connected in parallel with the resistance type electrical heating elements 64, 71, 72 which are also connected in parallel, as shown particularly in FIG. 11 of the drawings. A three-way switch 76 is connected ahead of the cover-actuated switch 74, and the switching element thereof is connected to the line. One contact 77 of the threeway switch 76 connects tothe switch 74, and the other contact 78 thereof bypasses the switch 74. The three-way switch 76, in addition to off position illustrated in FIG. 11, provides automatic operation through the switch 74 when the switching element engages contact 77 (this position not being illustrated). In this automatic position, the blower 66 and the heating elements 64, 71, 72 are on when the cabinet cover 38 is in its operative position and they are off when the cover 38 is in its inoperative position, although the blower 66 may be independently shut off by a blower switch 79 and any one of the elements 64, 71, 72 may be independently shut off by separate switches 80-82, respectively.

When the three-way switch 76 is in the position of engagement (not shown) with contact 78, a manual position is defined, so that the blower 66 is controlled only by the switch 79 and the elements 64, 71, 72 are controlled only by the switches 80-82 whereby when the switches 79-82 are closed, the blower 66 and heating elements 64, 71, 72 will be continually in operation. With this arrangement, the blower 66 or any or all of the heating elements 64, 71, 72 may be cut off as desired.

This invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the above objects; and while I have shown and described above a preferred embodiment thereof in which the principles of the present invention have been incorporated, I wish it to be specifically understood that the same may be modified without departure from the scope and spirit of the appended claims.

What is claimed is:

1. A refrigerated display cabinet including means for cooling the interior thereof and further comprising:

(a) spaced end walls and front and rear walls defining an open-top food case,

(1) said rear wall being of greater height than the end walls, and (2) the rear portions of the end walls having upwardly directed extensions,

(b) a top wall extending between the upper portions of said end wall extensions and defining with the rear wall a forwardly opening housing overlying the rear portion of said food case,

(c) a slidable cover overlying the open top of said food case, said cover having an elongated top wall, front wall and opposed end walls,

((1) the top wall, front wall and end walls of said cover being formed from a generally transparent plastic material and being molded as an integral one-piece unit,

(e) means mounting said cover for sliding movements on the cabinet end walls between an inoperative storage position within said housing and an operative position forwardly of said housing and covering the open top of said food case, and

(f) center guide means positioned generally intermediate the opposite ends of said cover, said center guide means comprising:

(1) an elongated generally horizontal center rail carried by said cabinet top wall, and

(2) an upstanding guide element mounted on the top wall of said cover adjacent the rear thereof and cooperating with the center guide rail during movements of said cover between its inoperative and operative positions.

2. A refrigerated display cabinet including means for cooling the interior thereof and further comprising:

(a) spaced end walls and front and rear walls defining an open-top food case,

(1) said rear Wall being of greater height than the end walls,

(2) the upper portions of said end walls defining generally horizontal supporting rails, and

(3) the rear portions of the end walls having upwardly directed extensions,

(b) a top wall extending between the upper portions of said end wall extensions and defining with the rear wall a forwardly opening housing overlying the rear portion of said food case,

(0) a slidable cover overlying the open top of said food case, said cover having an elongated top wall and depending front wall,

(d) means mounting said cover for sliding movements on the cabinet end walls between an inoperative storage position within said housing and an operative position forwardly of said housing and covering the open top of said food case, said mounting means comprising a pair of wheel-equipped carriages one each mounted at the opposite ends of said cover and riding on the horizontal supporting rails of said cabinet end walls, and

(e) center guide means positioned generally intermediate the opposite ends of said cover, said center guide means comprising:

(1) an elongated generally horizontal center rail carried by said cabinet top wall, and

(2) an upstanding guide element mounted on the top wall of said cover adjacent the rear thereof and cooperating with the center guide rail during movements of said cover between its inoperative and operative positions.

References Cited by the Examiner UNITED STATES PATENTS 1,896,346 2/1923 Bolhuis 312342 2,248,867 7/1941 Hallman 219-400 2,287,997 6/1942 Jarvis 62255 X 2,321,695 6/1943 Miller 62-248 2,479,135 8/ 1949 Ruthishauer 62-248 X 2,542,136 2/1951 Hanson 62--248 X (Other references on following page) 7 UNITED STATES PATENTS Fennell 312223 X Smith 62255 X Luecke 62-248 Luss 312-342 X Canter 312116 X Hargrave 62255 Werner 312116 X 8 FOREIGN PATENTS 7/1948 Canada. 6/ 1962 Great Britain.

5 CLAUDE A. LE ROY, Primary Examiner. 

1. A REFRIGERATED DISPLAY CABINET INCLUDING MEANS FOR COOLING THE INTERIOR THEREOF AND FURTHER COMPRISING: (A) SPACED END WALLS AND FRONT AND REAR WALLS DEFINING AN OPEN-TOP FOOD CASE, (1) SAID REAR WALL BEING OF GREATER HEIGHT THAN THE END WALLS, AND (2) THE REAR PORTIONS OF THE END WALLS HAVING UPWARDLY DIRECTED EXTENSIONS, (B) A TOP WALL EXTENDING BETWEEN THE UPPER PORTIONS OF SAID END WALL EXTENSIONS AND DEFINING WITH THE REAR WALL A FORWARDLY OPENING HOUSING OVERLYING THE REAR PORTION OF SAID FOOD CASE, (C) A SLIDABLE COVER OVERLYING THE OPEN TOP OF SAID FOOD CASE, SAID COVER HAVING AN ELONGATED TOP WALL, FRONT WALL AND OPPOSED END WALLS, (D) THE TOP WALL, FRONT WALL AND END WALLS OF SAID COVER BEING FORMED FROM A GENERALLY TRANSPARENT PLASTIC MATERIAL AND BEING MOLDED AS AN INTEGRAL ONE-PIECE UNIT, (E) MEANS MOUNTING SAID COVER FOR SLIDING MOVEMENTS ON THE CABINET END WALLS BETWEEN AN INOPERATIVE STORAGE POSITION WITHIN SAID HOUSING AND AN OPERATIVE POSITION FORWARDLY OF SAID HOUSING AND COVERING THE OPEN TOP OF SAID FOOD CASE, AND (F) CENTER GUIDE MEANS POSITIONED GENERALLY INTERMEDIATE THE OPPOSITE ENDS OF SAID COVER, SAID CENTER GUIDE MEANS COMPRISING: (1) AN ELONGATED GENERALLY HORIZONTAL CENTER RAIL CARRIED BY SAID CABINET TOP WALL, AND (2) AN UPSTANDING GUIDE ELEMENT MOUNTED ON THE TOP WALL OF SAID COVER ADJACENT THE REAR THEREOF AND COOPERATING WITH THE CENTER GUIDE RAIL DURING MOVEMENT OF SAID COVER BETWEEN ITS INOPERATIVE AND OPERATIVE POSITIONS. 